diff --git a/src/Compositor.cpp b/src/Compositor.cpp
index 78ee17b32..49aeb0e2c 100644
--- a/src/Compositor.cpp
+++ b/src/Compositor.cpp
@@ -2210,7 +2210,8 @@ void CCompositor::moveWorkspaceToMonitor(PHLWORKSPACE pWorkspace, PHLMONITOR pMo
     // finalize
     if (POLDMON) {
         g_pLayoutManager->getCurrentLayout()->recalculateMonitor(POLDMON->ID);
-        updateFullscreenFadeOnWorkspace(POLDMON->activeWorkspace);
+        if (valid(POLDMON->activeWorkspace))
+            updateFullscreenFadeOnWorkspace(POLDMON->activeWorkspace);
         updateSuspendedStates();
     }